Aeroplane.



R. B. SWANK.

AEBOPLANE.

APPLICATION FILED APR.17. 1913.

Patented Mar. 10, 1914.

6 BHEETSSHBET 1.

@Ivi/hamaca commun vLANoamml cn.. WASHINUTON. l, c.

R. B. SWANK.

AEROPLANE.

APPLICATION FILED APR. 17, 191s.

Patented Mar. 10, 1914.

6 SHEETS-SHEET 2.

R. B. SWANK. AROPLANB.

APPLIUATION FILED APR.17, 1913.

1,089,880. Patented Mar.10,1914

8 SHEETB-SHEET 3.

R. B. SWANK.

ABROPLANE.

APPLIGATION FILED APR. 17, 1913.

1,089,880. Patent-.ea Mar.10,1914

8 SHEETS-SHEET 5.

REUBEN B. SWANK, OF DAYTON, OHIO.

AEROPLANE.

Specification of Letters Patent.

Application fded April 17, 1913.

Patented Mar. 10, 1914.

sei-iai No. 761,768.

To all whom t may concern Be it known that I, REUBEN B. Swann, a citizenof the United States, residing at Dayton, in the county of Montgomeryand State of Ohio, have invented certain new and useful Improvements inAeroplanes; and .I do declare the following to be a full, clear, andexact description of the invention, such as will enable others skilledin the art to which it appertains to make and use the same.

rlhis invention relates to aeronautics, and more especially toaeroplanes; and the main object of the present invention is to effectimprovements on my prior patent dated March 19, 1912, and bearing number1,020,028.

More especially this is carried out by adopting an improved form of lockfor the tiller which controls the front runner, and a new form ofpivotal support for the upright shafts which drive the liftingpropellers, and by embodying in the machine manually controlled aileronsnear the lateral extremities of the framework and just inside saidlifting propellers, and manually controlled stabilizers or wings justinside the ailerons.

The invention further consists in the provision of a novel form ofmanually conw trolled tail or rear steering device.

The invention also consists in the details of construction used inconjunction with the novel features; all as more fully described in thefollowing specification and typically illustrated on the drawingswherein- Figure 1 is a diagrammatic rear end elevation, and Fig. 2 adiagrammatic plan view of this machine with parts broken away. Fig. 3 isan enlarged Central vertical longitudinal section, with the parts inrear of the section line omitted. Fig. 4 is an enlarged plan view of themachine with the right and left hand ends of its framework omitted andalso the upper plane omitted. Fig. 5 is a plan view of one end of theframework, Fig. G a rear elevation thereof, and Fig. 7 a verticallongitudinal section thereof. Fig. 8 is a section on about the line S--Sof Fig. 7, and Fig. 9 a section on about the line 9 9 of Fig. 6. Fig. 10is a section on about the line 10-10 0f Fig. 4, showing moreparticularly the manual control for the ailerons and the wings; and Fig.11 is a still further enlarged longitudinal section through saidcontrolling devices. Fig. 12 is a detail view in side elevation, andFig. 13

a similar detail in end elevation, of the manual control for adjustingthe angle of the axes of the lifting propellers. Fig. 14 is an enlargedsection on the line lflf 111- of Fig. 4, giving a detail of the improvedform of tiller lock. Fig. 15 is a detail perspective view of the tail.Fig. 16 is an enlarged elevation showing the form of connection betweenthe members of the frame, and Fig. 1 7 a vertical section through thisconnection. Figs. 18 and 19 are sectional views on the lines 153-18 and1,0-19 of Fig. 1G. Fig. Q0 is an enlarged plan view of the drivingpropeller. Fig. 91 is a diagram illustrating the hand control for thetwo ailerons.

Much latitude will be allowed to the builder of this machine withrespect to its framework F but as usual with air craft it will doubtlessbe made up of light sticks, rods or tubes rigidly connected at pointswhere they meet and properly braced by fine piano wire as seen in Figs.1G and 17, and, if the machine is a biplane which is my preferredconstruction, it will have upper and lower fixed planes l?, P extendingparallel with each other throughout the entire length of the transverseframework as best seen in Fig. 1, while forward extensions of saidfran'lework carry the steering rudder as seen in Fig. 2. Nor do I wishto be limited as to the details of the motor M, although preferably itwill be of high power and of the internal combustion type, mounted inthe dropped center of the framework at one side of the medial line orkeel thereof over which the operator is located, and counter-balanced by`machinery or tanks in a manner well known to engineers who arefamiliar' with structures of this character. Rubber-tired wheels willalso preferably be provided to support the machine while it is at reston the ground. For forcing the machine forward through the air I haveshown a special propeller I) driven by connection with the motor M, andthe fixed planes I), l.j are by preference disbed a little on theirunder side as seen in Fig. 3, and inclined slightly to a horizontal sothat the forward impetus of the driving n'leehanism lifts the weight ofthe machine and its occupants as long as the machine travels on an evenkeel.

Coming now to a more detailed description, rotary power iscon'nnunicated from the motor M through a main clutch C to the mainshaft 1, and from a power sprocket wheel 2 thereon by means of a chainbelt 3 to a sprocket pinion 4 on the shaft 5 of the propeller D which,as shown in Fig. 3, is

mounted rather high and just in rear of the uppermost plane P; and it isthe forward 5 impulse imparted to the machine by this driving propellerD, combined with the slight inclination possessed by the planes P, whichsustains the machine in its flight through the air.

The rudder R for steering this machine is disposed at the forward endthereof and is shown herein as constructed much as in my prior patentabove referred to. It is composed of two substantially horizontal planes10, 10, crossed by two upright and normally longitudinal planes 11, 11,the whole pivotally supported on the front end of the framework F andthe upright planes connected at front and rear by rods 12 and 13 as bestseen in Fig. 4. The last-named rod has a pin 14 loosely engaging a slot15 in the front end of the tiller 16, and said tiller is mounted on auniversal joint 17 at about the center of its length, while its rear endcarries a hand wheel which may be raised or lowered or moved from sideto side to adjust the position of the rudder in a manner wellunderstood. My improved means for locking the position of this tiller,best seen in Fig. 14, comprises a cross bar 19 through which the tiller16 passes, a frame 2O having upright slots 21 in its side bars withinVwhich the cross bar 19 moves freely, and around each side bar and overeach end of said cross bar a clip 22 whose arms pass through a clipplate 23 and which latter carries a hand screw 24 as shown. W hen thesescrews are loosened the clips permit the vertical and lateral movementof the cross bar 19 as the tiller 16 is moved within the frame 20, butat any time it is desired to lock or set the tiller in one position thehand screws 24 are tightened up and they clamp the cross bar 19 in theposition it then occupies within the frame.

An important feature of the present invention lies in the use of aspecial form of tail T, best seen in Fig. 15, and shown in use in Figs.2 and 3. This tail in addition to its framework comprises an uprightplane or fin 30 and a substantially horizontal lane 31 which crosses theupright fin but which is itself curved longitudinally a little as seenin Fig. 3; and from the point where these planes intersect a rod 32leads forward through suitable bearings 33 to a hand wheel 34 whichpreferably carries a spring-actuated plunger 35 adapted to enter any ofa number of sockets 36 in a plate 37 fixed adj acent said wheel, wherebythe latter is locked in any position to which it is adjusted. Bywithdrawing this plunger from a certain socket and turning the wheelproperly, the rod 32 sets the tail as may be desired.

: When set as shown in Fig. 3, the slight curtaining planes, although itworks against the rudder by raising the rear end of the machine slightlyand therefore tending to tip the front end downward.. 1When the handwheel is reversed so that the dish of the curved plane 31 is the otherside up, it will be clear that it acts in opposition to the main planesP, and the rudder R must be adjusted accordingly. When, however, theoperator sets this tail at quartering post tions between the twoextremes just described, so that the curved plane 31 standssubstantially vertical as seen in Fig. 2, it will be clear that itserves in the nature of a rudder at the rear of the machine the same asthough the tail of a fish were inclined a little to one side. This useof the tail may be rare if the rudder R is in good working order or ifit be sufficient, but apprehend that on occasions it may be extremelyvaluable to have an additional rudder which may thus be thrown intoaction by a simple turning of the handwheel 34 to its proper position.Manifestly a skilful operator may set the tail in such manner that itscurved plane 31 will stand oblique so that he may secure both thevertical and kthe horizontal results of its curvature.

As in my prior patent above referred to, .1 preferably employ liftingpropellers L at the extreme side ends of the framework F, each of whichis mounted on an upright shaft 40 and driven from the motor M bysuitable connections. rlhe latter as illustrated consist of a drivepulley 41 fast on the lower end of the shaft, and a belt'42 leading fromthe same over suitable guides or idle pulleys such as those numbered 43,to a driving pulley 44 mounted loosely on the main shaft 1 and adaptedto be thrown into connection therewith by a clutch mechanism under thecontrol of the operator. Two such driving pulleys and clutches are shownin Fig. 3, and obviously when these are separately connected with thetwo lifting propellers L at opposite sides of the machine, either may bethrown into action irrespective of the other. rllie lower end of theupright propeller shaft 40 is stepped in a bearing block 46 (see Fig. 7)which in turn is pivoted between two side pins 47 in the frame F so thatthis block may rock forward and backward; and the upper end of saidshaft is journaled in a rack bar 43 which is movable through suitableguides 49 in the framework F, said rack bar being engaged by a gearwheel 50 fast on a shaft 51 mounted in bearings 52 across the uppermostplane P as best seenin Fig. 1. This shaft at its center carries asprocket gear (Figs. l2 and 13) connected by a chain belt 5ft with asimilar gear on the shaft of a hand wheel which is ournaled in astandard 56 and adjustable therein by any suit able means, such as thosealready described with reference to the hand wheel on the rod 3Q whichcontrols the disposition of the tail. By turning this hand wheel 55 andsettilrcy it fast, the chain belt imparts rotary motion to the shaft 5l,and the latter through its gears 50 moves the 'ack bars it9 so that theupper ends of the upright shaft l() of the lifting' propellers are movedeither forward or backward. Hence i't is possible for the operator toadjust the angle of these shafts ll() and therefore the axes of saidlifting propellers, and it is obvious that when the shafts are caused toincline forward the propellersI will not only lift the machine butassist in its propulsion, whereas when the shafts are inclined to therear the propellers will resist the forward as well as the downward`nnivement of the machine and may be utilized in making a landii'in'.Ordinarily, however, these lifting propellers are e1n ployed atstarting' or when the aviator desires to ascend, and their shafts aretilted forward and thrown into action conjointly with the propelling,-mechanism only at times when such conjoint action becomes neces sary ordesirable. Attention is directed to the fact that while these liftingpropel ers may be independently thrown into or ont of connection withthe main shaft l, their angles are adjusted simultaneously by a singlecontrolling' device as described. Next inside 'the lifting propellers(and by preference between the two ixed planes as seen in Fig. G,whereas said propellers are heyond the extremities of such planes) arehinged planes (herein called ailerons n) as best seen in Finis. 5, 6, 7and 9, and as they are alike I will describe but one. Hinged at G0 tothe forward cross bar of that portion of the frame which carries theupper fixed plane P is a plane much like it in transverse section andwhich will doubtless be made of a like frame covered over with fabric,but each aileron A should have suhstantially the same curvature as theplane P above it as shown in Fig'. 9 so that when completely raised itwill hare no etteet on this end of the machine. 'lhrounh the aileron nlat a suitable point is formed a slot Gl, and adjacent the same at thepoint G2 is connected a cord GS which leads upward over a pulleyGilcarried by the upper fixed plane l or the frame thereof, and thencedownward through the slot G1 along 'with a seeond stretch of cord (35which leads directly downward from 'the point (32. These two stretchesare led thence through suitable guides or over idle pulleys G6 andeventually pass in opposite directions around a groove 67 in a drum GS,best seen in Figs. ll and 2l.

Similarly the two stretches of cord from the aileron at the opposite endof the frame l" are led around another `groove (37 at the other end ofthe drum. The latter is controlled by a hand lever G9 by n'ieans ofwhich it'. can be turned on its sujpiporting shaft TO, and after its:n'ljustment it may be held against a shoulder Tt on said shaft by meansol a hand nut 72 which is threaded on t'he .shaft at 723. llenen then'ianipulation of the hand lever Gt) turnsl the drum (3S, and throughthe two pairs of cords this raises one aileron and lowers the other.)Vlien either 'is raised into or substantially into contact with theuppermost plane l, its influence on the machine practically disappears,but when it is lowered as seen .in liin'. t) it tends to raise themachine at this side, whereas the rudder at the front edge of themachine is for adjustinj.;` the forward end of the whole machine and thetail l for adjustine,` the rear end thereof. These three elements arelikewise serviceable in descend ing or in soaring' when possibly therotation of all propellers has ceased, and as they may be adjustedhulepeiulently ol' each other the aeronaut can descend or soar at willdespite the disquietingg inlluence of cross currents of air.

l have stated above that the disposition of the motor, the tanks, andother heavy pieces of inerhaniinn at the dropped center of the frameworkl" is for the purpose of holdinp` the machine on an even keel, but it iswell known to those familiar with this art that other means aredesirable if not necessary for in'iparting stability to an aeroplane.For this purpose l have employed other hinged planes (herein calledstabilizers) located between the two lixed planes l. next inside theailerons` and as they ari alike a description of one will sutlice forboth.

As best seen in itin'. S, each stabilizer S consists of two wings 8O andSil, thefornier hingedly conneiifted at 81 with the rear :frame-lair Fof the upper plano l", and the wing Sil pivotally or hingedly connectedwith the wing' SO on a line S2, wlufreas the front end of the wing S53moves over guide rollers 8l; and under the front cross bar S5 of saidframe. ltlaeh of these wings, like the ailerons, will doubtless bectmslructed of a light framework over 'which is stretched a light canvassheet, and their size with .reference to that of the planes will heabout in the j n'oportion illustrated in l and 2. l `rom the hinge line552 of each stabiliser, and at; the outer end of the frame as seen inFig. 7, a stretch of cord Sti passes upward over a pulley Si and anotherstretch Si) passes directly downward, and these two stretches leadthence inward through suitable` guides or over suitable idlo pulleys 5%and pass eventually in opposite direciioia; around. a groove 97 in adrum 98 which is kann actuated by a hand lever 99 and is journaled on anenlarged section 100 of the shaft 70 best seen in Fig. 11; correspondingstretches 86 and S9 from the opposite end of the hinge line 82 passingthrough similar guides or over similar idle pulleys 88 to ano-thergroove 97/ at the other side of the drum 98. 1t will be but a.duplication of the description and reference lettering to state that thestabilizer S at the opposite end of the frame F is connected by cords ina similar manner with another and identical conH trolling deviceillustrated at the center of Fig. 11. The two drums of these controllingdevices are rot-atably mounted on the enlarged section 100 of the shaft70 between plates 101 which engage square portions 102 of said shaft atopposite ends of its enlarged portion, and neXt outside said squared portions the. shaft is threaded as at 103 to receive hand nuts 10st` bymeans of which the parts of these controlling mechanisms are assembled.The extremities of the shaft are by preference squared as at 105 and litin standards 106. Said plates 101 carry spring-actuated plungers 10'(-engaging sockets 10S in the drum, and when the plungers are withdrawnthe drums may be set by means of their hand levers as they will thenturn freely in either direction on the enlarged section 100 of theshaft. But it should be observed that, whereas the single hand lever 69and single drum 68 control both ailerons A, there are twovindependentdrums with their hand levers and locking mechanism for controlling thestabilizers, and the cords leading from each drum lead to both ends ofthe stabilizers because the latter are lerger than the ailerons, moreoften brought into use, of greater necessity when they are used, andtherefore demand stronger cont-rol. By turning one of the drums 98 inthe proper direction, the hinge line 82 will be depressed seen in Fig.8, whereby the wing 80 turns around its pivotal point 81 and the wing 88moves downward at its inner edge and the outer edge slides between therollers Si and frame-bar 85; by turning the drum 98 in the oppositedirection, the other stretch of cord S0 draws upward on the hinge lineand the stabilizer may be folded against the uppermost nl, P so as tolie practically coin ilent therewith. These devicesare/useful when Itheair craft is unbalanced and tenus to tip to one side and so, as it ismost frequently indmed to do by reason of cross currents or by its beingoverloaded on one side or the other, but these devices are also usefulfor purposely 'tilting the air craft on its keel as when the aviatorintends to sail in a circle. Moreover the stabliaers may be employed indescending, because when their hinge lines 82 are down to a considerableextent they aiiord a certain element of resistance :message to the airpassing between the planes P, l?. However, in their ordinary use theindependent control of the stabilizers at opposite ends of the mainframework will obviously be necessary.

The specific connection employed between the sticks or members of theframe is best seen in Figs. 16 to 19 inclusive. ln these views ahorizontal stick or member 110 carries a metal plate 111 bolted to it asatr112 and having an upstanding integral socket 113 for receiving thelower end of an upright member 111-, which latter is slottedlongitiulinally above its lower end as at 115. rllwo other bolts 116pass downward through the plate 11.1 on the member 110 with their bodiesstanding alongside the member 114i and ha Ying bends 117 to receive thepiano wire braces as indicated in dotted lines at 11S, and the upperends of these bolts are connected by a cross bolt 119 which passesthrough the slot 115 in the member 114. With this construction thetightening up of the wires 118 by means of the turn buckles ordin llyemployed within their length the latter it is communicated through theplate 111 to the lower side of the horizontal member 110. rllhe uprightmember 1141 meanwhile acts a spacer, its lower end resting in the socket113 on the plate 111 and its upper end resting within a similar socketbeneath, the overhead horizontal member `(not shown) so that these twohorizontal membersV are properly spaced no matter what the tension ofthe wires 118. lf the parts should rattle just before any adjustment,the nut on the bolt 119` is loosened, so that afterward when it istightened up all rattling is prevented.

The driving propeller' D whereof an enlaro'ed elevation is given in Fig.20 comprises a hub 120 mounted on the main shaft 1 by any suitable meanssuch as the nut 121 and the jam nut 122, and two blades or tiukes 123extending from diametrically opposite sides of this hub in a mannerwhich is usual in propellers for flying machines. ly preference l wouldmake these blades of tough but light/voeder of Vlight metal such mi/inn,but their specific construction such that, while their pitch or twistmay dit vler at different points radially outwardfrom the axis, there isno point where they stand in a plane at right angles to such axis andtherefore every square inch of each blade or fluke will impart a thrustto the flying` machine.

l do not wish to be limited to details or materials of parts furtherthan as set forth by the claims l elow.

Thus will be seen that l have produced an air craft which is hereinillustrated and preferably constructed with parallel planes although ofcourse it might have but throws the strain onto the bolts 116 and byv asingle plane or there might be more than two; and although the operationand control of these .machines .is well understood I may brielly repeatit here. The aviator with his passenger or assistant boards the cra'ltand the engine is started. The main clutch. il closed and the drivingipropeller i) l'iegjins to rotate. The clutches l5 are closed, and theli'ltiire propellers L begin to rotate. Hoon their power .lifts themachine oli its supifiortinel wheels and the Ytorce of the drivingmechanism D starts it lorward, and then the rudder ,t (and possibly thetail T) with or without the stabilizers S but preferably with theailerons A, are thrown into action to assist the machine to rise.fiiaving attained the proper altitude the stabilit/.ers and ailerons arefolded up near the upper plane l?, and under normal con` ditions themachine may be easily guided horiz/,ontally and vertically by means o'l1the rudder li and its tiller, or the latter may be locked and themachine guided by means of the tail T. ll the aeronaut encounters crosswinds or ohlique currents, itmay become desirable it not necessary toset the proper stahiliaer ,fil by means of the control mechanism. bestillustrated in Fig. 11.; or the proper stabilizer is thrown into actionin ease he desires to turn about in a circle or curve and in which eventthat side o'l the machine which is on the outside of the curve would have to be raised. Vfhen he desires to ascend to a greater altitude, hewill mal-fe use oi both the rudder li and tail T, and possibly also ot.'both stabilizers, although these should be ordinarily used to keep then'iaehine on an even keel; and if he desires to ascend rapidly he maythrow the lilftinir propellers into action in a manner which will beclear, although the. power necessary to drive these propellers mayordinarily be saved and imparted to the driving` propeller l). ln orderto descend or to soar, the same elements are used in the rcverse mannerexcepting' that it would not be desirable to employ the lifting;`propellers at that time. The rudder .lt and tail T may be used singly orconjointly, but in this case the ailerons A will doubtless be 'foldedupward near the upper plane P. .Tn rase 0i accident so that the speedoit descent increases until the machine is almost falling, the aviatorhas lout to throw the lifting); pro pellers into action and his :t'allis arrested. Yit the accident be such as to put his motor M out ofcommission, the aviator can save himself a itall hy the combined use oitthe rudder, tail. both ailerons, and even both stabilizers it necessary,for when all are in action the machine will soar to the ground.

What is claimed as new is:

l. In an aeroplane, the combination with a framework dropped at itstransverse Center to afford space for the operator, a forward rudder, arearward tail, controlling` devices t'or these elements at the center ofthe machine and respectively in front and rear ot' said space, and adriving propeller mounted on a shaft standing along,` the center 0f thetraine; oi a motor and its main shaft disposed to one side of saidspace, connections hetween this shaft and that ot' the drivingmechanism, hinged planes at the extremities oitl the iframe, manualcontrols therefor located at the opposite side of said space from saidmotor, and connections between said planes and their respectivecontrols.

Q. The herein described air craft comprising fixed main planes extendingtransversely oit the machine, lifting propeller-s at the extremities ofsaid planes, two pairs of hinged planes next inside said propellers,manual means for adj listing them, a rudder at the iti-ont oi themachine, a, longitudinally curved tail at the rear end oi? the machine,means for turning,Y this tail on its longitudinal axis, the drivingmechanism, and a power plant.

3. The herein described air crat't comprising fixed main planesextending transrersely ot the machine, lifting,r propellers at theextreu'lities of said planes, hinged planes next inside said propellers,means for adjusting them, a rudder at the t'ront of the machine, alongitudinally curved tail at the rear end o'l the machine, means -forturning this tail manually on its longitudinal axis and setting it inadjusted position, the driving mechanism, and a power plant.

fl. The herein described air cra't't comprising Ixed main planesextendingl transversely of the machine, hittingpropellers near the endsof said planes, hinged planes adjacent said propellers, means Yforadjusting,r them, a rudder at the :front of the machine, alongitudinally curved tail at the rear endet the machine, means lorturning this tail on its longitudinal center and setting it in adjustedposition, the driving mechanism, and a power plant.

5. The herein described air craft compris ing fixed main planesextending transversely of the machine, lifting propellers at theextremities of said planes, hinged planes inside said propellers, meansfor adjusting said hinged planes independently of each other, alongitudinally curved tail at the rear end of the machine, the drivingmechanism, and a power plant.

G. In an aeroplane, the combination with the framework, a main planeextending transversely of said framework, and the propelling' andsteering mechanisms; o'l a movable plane at each end of said frameworkcomprising two wings hingcdly connected with each other at a point belowsaid main plane, a pivotal connection between the rear edge of one wingand the framework near the rear edge of said main plane, a slidingconnection between the other wing and the forward edge of said mainplane, and means for adjusting the hinge line between said wings.

Y. In an aeroplane the combination with the framework, a lined planeextending transversely of said framework, and the propelling andsteering mechanisms; of a movable plane at each end of said frameworkcomprising two wings hingedly connected with4 each other at a pointbelow said plane, a pivotal connection between the rear edge of one wingand the framework near the rear edge of said main plane, a slidingConnection between the other wing and the forward edOe of said mainplane, pulleys carried beneath said iiXed plane at each end of saidhinged plane, and from each end of the hinge line between its wings astretch of cord leading upward over one of said pulleys and downward andanother stretch of cord leading from said hinge line downward, both saidstretches being led through suitable guides to a controlling devicewithin reach of the operator.

8. ln a biplane, the combination with superimposed iiXed main planesmounted on a framework extending transversely of the machine, and thepropelling' and steering mechanisms; of a movable plane hinged at itsfront edge to the front edge of the uppermost main plane near each endof the latter, means controllable by the operator for raising andlowering the rear edges of said hinged planes in opposition to eachother, other movable planes next inside those mentioned and at oppositeends of said main frame, each consisting of two wino's whereof therearmost is hinged to the framework near the rear edge of the uppermostiXed plane, and the foremost is hinged to the front edge of the rearmostand slidably Losses() mounted in the front edge of said uppermost fixedplane, and means under the control of the operator for raising andlowering the meeting edges of eachy pair of wings independently of theadjustment of the meeting edges of the other pair of wings.

9. In a biplane, the combination with superimposed main planes mountedon a framework extending transversely of the machine, and the propellingand steering mechanisms; of a movable plane hinged at its front edge tothe front edge of the uppermost main plane near each end of the latter,means controllable by the operator for raising and lowering the rearedges of said hinged planes, other hinged planes at opposite ends of theframework and beneath the uppermost main plane, each including a winghinged at its rear edge to the framework near the rear edge of said mainplane and adjustable vertically at its forward edge, and means foradjusting said wings.

l0. ln a biplane, the combination with parallel fixed main planessuperimposed one above the other and slightly dished on their undersides; of two wings hingedly oonnected with each other and also slightlydished to correspond with the dish of the uppermost plane, said wingsbeing located between the fixed planes and hingedly mounted along theouter edge of one wing, and means for adjusting the angle of `said wingsto each other or for raising the wings into substantial parallelism withthe upper plane.

ln testimonyv whereof I have hereunto set my hand in presence of twosubscribing witnesses.

REUBEN B. STWANK.

lWitnesses JOHN d. HOOVER, F. lvfAUDn HOOVER.

@opea of this patent may be obtained for ve cents each, by addressingthe Commissioner of Patenti! Washington, D. C."

